CVE-2026-118180
Matrix homeserver could redirect the chat session to a local file or network share
- State
- Published
- Severity
- Not scored
- Published
- Oct 27, 2026
- Updated
- Oct 27, 2026
- Reserved
- Oct 27, 2026
Description
When logging in to a Matrix account, Thunderbird used the homeserver address provided in the server's login response without validating it. A malicious or compromised homeserver could provide a file: URL, causing Thunderbird to send all further Matrix requests of that session to local files or, on Windows, to an attacker-controlled network share, which could leak the user's NTLM credentials. The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.
Scores
The record has no CVSS score.
Weaknesses
The record names no weakness.
Affected Products
| Product | Versions |
|---|---|
ThunderbirdMozilla |
|
References
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